The present invention relates generally to pumps and, more particularly, to a pump having a heat-actuated diaphragm which is formed using microfabrication techniques.
There are many processes in which a relatively small quantity of fluid, either gas or liquid, must be dispensed in a measured amount. One typical process of this type is the process of liquid chromatography in which a precise amount of liquid in a quantity of e.g. 1 microliter must be dispensed to a separation column. In applications in which such small quantities of fluid are to be dispensed by pump, a difficulty in precise metering arises if the pump chamber is relatively large as compared to the quantity of fluid which is to be dispensed. The construction of pumps with extremely small pumping chambers has heretofore proven to be difficult and expensive.
Certain microfabrication techniques for constructing valves are described in U.S. Pat. Nos. 4,821,997 and 4,824,073 of Zdeblick and in U.S. Pat. application Ser. No. 560,933, filed Jul. 31, 1990, of Beatty and Beckmann for Control Valve Using Mechanical Beam Buckling, each of which is hereby specifically incorporated by reference for all that is disclosed therein.